1. Field of the Invention
The present invention relates to an image converting apparatus for eyesight handicapped persons in which optical image data such as characters, symbols, or the like or electrical image data is input and converted into vibration patterns, and these patterns are output and displayed by a sensing display device consisting of an array of transducers arranged in a matrix form.
2. Related Background Art
The first content of the conventional technique will be first described.
Such a kind of sensing display apparatus has been put into practical use as a reading apparatus for blind persons in which characters, symbols, or the like which were optically read are converted into electric signals and displayed by the projecting vibrations of a tactile array on a Bimorph tactile array arranged in a matrix form, thereby enabling the image data to be sensed by the finger tip. As patent references regarding such an apparatus, for example, there have been known a scanning apparatus disclosed in Japanese Patent Publication No. 43424/1981, a power source checker disclosed in Japanese Patent Publication No. 46081/1981 an optical/mechanical converting apparatus disclosed in Japanese Patent Publication No. 46854/1981, and the like.
FIG. 2 is a schematic perspective view of a reading apparatus for blind persons which has conventionally been used. In FIG. 2, when a camera unit 101 is put on a paper 103 and moved on the paper, data such as characters, symbols, or the like which was read by the camera unit 101 is output as projecting vibrations on a tactile array 105. The tactile array 105 consists of (5.times.20) pins arranged in a matrix form. For example, when the camera unit 101 is located on a character "T" on the paper, the individual pins of the tactile array project and vibrate in a form of "T". The blind person senses these vibrations by the finger tip, thereby recognizing the character "T".
However, in the case of recognizing the character "T" by the conventional reading apparatus for blind persons, an instructor who can see repeatedly slides on the character "T" by the camera unit 101 many times while looking at the character "T", and the blind person learns a pattern of character "T" by being taught by the instructor. In this manner, the blind person must train. Thus, a long training period is needed.
As described above, the blind person needs to train for a long time and the instructor to instruct this training is necessary until the blind person can skillfully operate such an apparatus. Therefore, this drawback makes it difficult to spread such a kind of apparatus. These drawbacks are set to the first problem.
The second content of the conventional technique will now be described.
FIG. 7 is a perspective view showing a constitution of a reading apparatus for blind persons which has conventionally been used. In FIG. 7, when a camera unit 201 is put on a printed matter 203 and moved in the direction indicated by an arrow on the paper, the data such as characters, symbols, or the like which was read by the camera unit 201 is output as projecting vibrations on a tactile stimulator 205. The tactile stimulator 205 consists of (5.times.20) pins arranged in a matrix form. For example, when the camera unit 201 is located on a character "T" on the printed matter, the individual pins of the tactile stimulator project and vibrate in a form of "T". The blind person senses the vibrations by the finger tip, thereby recognizing the character "T".
On the other hand, when a single instructor instructs two blind persons, as shown in FIG. 7, another main unit 204' having a tactile stimulator 205' is connected to a main unit 204 by a connecting cord C.sub.1. In the case of instructing three blind persons, another main unit 204" is connected to the main unit 204' by a connecting cord C.sub.2. In such a case, if a failure occurred in the connecting cord C.sub.1, camera unit 201, or main unit 204, not only the tactile stimulator 205 of the main unit 204 but also the tactile stimulator 205' of the main unit 204' and a tactile stimulator (not shown) of the main unit 204" cannot be used. If the main unit 204 failed, the camera unit 201 is detached from the main unit 204 and the connecting cord C.sub.1 is disconnected from the main unit 204'. Thereafter, the camera unit 201 is connected to the main unit 204'. Thus, the tactile stimulators of the main units 204' and 204" can be used. However, as mentioned above, it is troublesome to again connect the camera unit 201, connecting cord C.sub.1, and the like and it is very inconvenient. These drawbacks are set to the second problem.
The third content of the conventional technique will now be described.
Hitherto, as one of such a kind of pattern reading apparatuses, as shown in e.g. Japanese Patent Publication No. 46854/1986, there has been put into practical use a reading apparatus for blind persons in which a pattern which was optically read by a camera unit is converted into an electric signal, and by vibrating a Bimorph tactile array arranged in a matrix form, the read pattern is displayed. However, in such a conventional apparatus, the input signal from the camera unit is compared with a threshold voltage by a comparator, and the read pattern is binarized into a light portion and a dark portion.
Therefore, when the voltage difference between the light portion and the dark portion in the output signal of the camera unit is small, the output signal of the camera unit is easily influenced by the noise component included in the threshold voltage (reference voltage which is input to the comparator). In particular, in the case of reading an image of a low contrast such as a colored original document or the like, there is a drawback such that it is difficult to adjust the threshold level. In addition, there is a drawback such that a display pattern easily flickers or the like due to the noise component. These drawbacks are set to the third problem.
The fourth content of the conventional technique will now be described. As mentioned above, it is necessary to train for a long time until the blind person can certainly read by the finger tip the data such as characters, symbols, or the like which is output and displayed on the sensing display device to display the read pattern as a tactile pattern. In such a training, it is demanded to use personal computers, which have particularly been spread in recent years. However, in the conventional apparatus, an output signal of the personal computer cannot be input.
Further, to improve the training efficiency, it is demanded to simultaneously output the same output pattern to a plurality of similar sensing display devices by an output signal of a single input apparatus. However, such a demand cannot be realized.
On the other hand, in general, eyesight handicapped persons such as blind persons or the like who use the foregoing conventional reading apparatuses are superior in the tactile-reading of Braille. There are many requirements for an apparatus to convert electric image data signals or data signals from various kinds of external terminal apparatuses into Braille. However, the conventional apparatuses cannot satisfy such requirements. These drawbacks are set to the fourth problem.
Further, the fifth content of the conventional technique will be described. The foregoing image converting apparatus is always carried and used by a blind person. Therefore, a battery must be used as a power source because of limitations of size, weight, and the like. By use of a battery as a power source, those limitations can be eliminated. However, the user is anxious since he cannot know a remaining battery's capacity. There is a possibility such that the operation of the apparatus becomes unstable due to a voltage drop by the lack of battery capacity. When a wrong pattern is output, the user may erroneously recognize it. To prevent such a misrecognition, it is necessary to save an electric power consumption of the battery. For this purpose, the user repeatedly frequently turns on and off the power switch to thereby prevent a vain consumption of the battery power.
However, hitherto, the discrimination and execution of the on-off operations of the power switch as mentioned above are performed by the will of the user. Therefore, in such a kind of apparatus, not only is fatigue produced by tactile-read characters or the like but also fatigue due to the on-off operations of the power switch is further added. Thus, the erroneous tactile-reading increases and the tactile-reading operation for a long time will be impeded. In addition, since the user is blind, there is a drawback such that the user must search for the power switch. These drawbacks are set to the fifth problem.